Tactical in a RSV with repulsors3 or GW3 can do quite potent damage.. For TBR3 you need to buff up, then fire up evasive and simply push the enemy away (works great with a escort friend that know your tactics, so he can follow out and pump DHC fire into them)
Sci can do nasty nasty feedback with FBP3. (but this is a passive build)
Havent flown SVs too much, but Ive had good success with builds based on those powers.
I'll second that. A tac in a rsv is very fun to fly and can be very dangerous. Over 100 power to weapons and aux. And go.
And I'll run 2 copies of hy1 with that too. And target shields2... Oooohhh, spec into ops, sensors and sensor array, maybe a console or 2 to boost the array. You will just be astonished at how much acc weapons will take down shields. After that my fav combo for a tac in a sci is trac beam and grav well. that grav well can do supprising damage, and since you are dropping shields all the better.